C4 Smog Pump
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
C4 Smog Pump
I'm working on a 87 Vette OEM smog pump... I tried posting this on the C4 section but nobody seems to be experienced with smog pumps over there. I have it apart up to the point where I have the drum in my hand.
1) Unbolted the pulley
2) Gently pried the plastic fan off the hub (not necessary for 87 pump as it turned out)
3) Made a tool to pull the hub (steering wheel puller too big)
Here is a pic of the tool I made to remove the front hub:
(3) 8mm 1.25 x 60mm bolts
(1) 1/2-20 nut
(1) 1/2-20 bolt
(1) hose clamp
+ a small socket to mesh with the pump shaft while pressing
4) Removed the (4) rear cover bolts
5) Carefully separated the two pump housing sections
6) Pressed the drive shaft & drum out of the front housing/bearing (Z99503)
The internal needle roller bearings in the arms that support the vanes are all dried up and spoogy. They need to be cleaned & re-greased. This is the part(s) that was bound up.
The vane supports cannot be removed without removing the rear "cup" of the drum. There are two tiny stake marks on the drum at 180 degree's to each other, indicating the "cup" (holding the rear bearing) is screwed in rather than pressed in.
Drum Pic:
http://i64.tinypic.com/2rfpj6b.jpg
Question: How does this a come apart? Pressed or screwed?
1) Unbolted the pulley
2) Gently pried the plastic fan off the hub (not necessary for 87 pump as it turned out)
3) Made a tool to pull the hub (steering wheel puller too big)
Here is a pic of the tool I made to remove the front hub:
(3) 8mm 1.25 x 60mm bolts
(1) 1/2-20 nut
(1) 1/2-20 bolt
(1) hose clamp
+ a small socket to mesh with the pump shaft while pressing
4) Removed the (4) rear cover bolts
5) Carefully separated the two pump housing sections
6) Pressed the drive shaft & drum out of the front housing/bearing (Z99503)
The internal needle roller bearings in the arms that support the vanes are all dried up and spoogy. They need to be cleaned & re-greased. This is the part(s) that was bound up.
The vane supports cannot be removed without removing the rear "cup" of the drum. There are two tiny stake marks on the drum at 180 degree's to each other, indicating the "cup" (holding the rear bearing) is screwed in rather than pressed in.
Drum Pic:
http://i64.tinypic.com/2rfpj6b.jpg
Question: How does this a come apart? Pressed or screwed?
Last edited by Tom454; Feb 13, 2016 at 12:03 PM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
I know what you talking about,,,BUT I have not had to do what you want due to being able to free up the vanes and get it to spin and work correctly.
I have an old smog pump that I can destroy to see how it is assembled...but I am so busy..literally..it can take a while for me to be able to get to the destruction mode.
DUB
I have an old smog pump that I can destroy to see how it is assembled...but I am so busy..literally..it can take a while for me to be able to get to the destruction mode.
DUB
Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
I'm gonna go out on a limb and guess that its internally similar to the one on my 68. If it is, its pressed in. It looks like there are holes on the "cup"for some kind of spanner wrench but theyre not. Heres a thread I started with some pics.https://www.corvetteforum.com/forums...mp-devane.html
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
I'm gonna go out on a limb and guess that its internally similar to the one on my 68. If it is, its pressed in. It looks like there are holes on the "cup"for some kind of spanner wrench but theyre not. Heres a thread I started with some pics.https://www.corvetteforum.com/forums...mp-devane.html
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
The cup is pressed in. I used a slide hammer to remove it. Unfortunately, that method completely ruined the rear bearing. I had a feeling this was going to happen, but I saw no other way to get the cup out of the barrel.
I would have gotten away with just replacing the bearings, but I forced one of the small curved "shoes" and it shattered. Have no idea where to get a new set of shoes. Also, the INA FC 66555 rear bearing is the Holy Grail.
INA FC 66555 Rear bearing slide hammer damage:
Broken “shoe”: (+ rails + springs)
(the “shoe” is the smaller curved ceramic piece)
Ceramic insert retainer inside the barrel- 2 shoes go on top and 2 on the bottom:
(Rails & springs in the long slots)
Z99503 Drive end bearing with plastic pin retainer:
J-65 Torrington Vane support needle bearings (4):
I’ve contacted several pump rebuilders and they are unwilling to sell me any parts… they feign ignorance.
I guess I’ll buy a reman from Rockauto and transfer what I need.
I would have gotten away with just replacing the bearings, but I forced one of the small curved "shoes" and it shattered. Have no idea where to get a new set of shoes. Also, the INA FC 66555 rear bearing is the Holy Grail.
INA FC 66555 Rear bearing slide hammer damage:
Broken “shoe”: (+ rails + springs)
(the “shoe” is the smaller curved ceramic piece)
Ceramic insert retainer inside the barrel- 2 shoes go on top and 2 on the bottom:
(Rails & springs in the long slots)
Z99503 Drive end bearing with plastic pin retainer:
J-65 Torrington Vane support needle bearings (4):
I’ve contacted several pump rebuilders and they are unwilling to sell me any parts… they feign ignorance.
I guess I’ll buy a reman from Rockauto and transfer what I need.
Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
I’ve contacted several pump rebuilders and they are unwilling to sell me any parts… they feign ignorance.
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
In cases like this where the parts are basically made out of 'unobtainium'...that really sucks because you get so close and then hit a brick wall where jerks who do it... do not want to help....even when you want to pay for the parts.
DUB
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Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
On the bearings... If you really want to find them and using the numbers doesn't help, you can always look them up dimensionally. All the major manufacturers(SKF, Timken etc.) have their catalogs online and I'd be willing to bet one of them will make a bearing that'll work. Might save a bit of money over buying a rebuild and pulling it all apart for some bearings. That being said, there is something convenience wise to be said for buying a rebuilt unit and just bolting it on.
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
On the bearings... If you really want to find them and using the numbers doesn't help, you can always look them up dimensionally. All the major manufacturers(SKF, Timken etc.) have their catalogs online and I'd be willing to bet one of them will make a bearing that'll work. Might save a bit of money over buying a rebuild and pulling it all apart for some bearings. That being said, there is something convenience wise to be said for buying a rebuilt unit and just bolting it on.
The rear bearing is kind of unique... it is a needle roller bearing, flanged on one side. The other ones are readily available.
INA FC-66555 is not even listed on INA's web site in Germany.
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Update on the INA FC-66555....
After going roundy-round with INA they finally acknowledged that FC-66555 is indeed the correct rear bearing number. However.... it is out of production. Going by the specs of 1.5 ID x 1.875 OD x 0.5 width and:
Drawn Cup, Caged Shell, Open End, Non-Sealed Roller Needle Bearing we came up with a new number: SCE248.
Readily available.
After going roundy-round with INA they finally acknowledged that FC-66555 is indeed the correct rear bearing number. However.... it is out of production. Going by the specs of 1.5 ID x 1.875 OD x 0.5 width and:
Drawn Cup, Caged Shell, Open End, Non-Sealed Roller Needle Bearing we came up with a new number: SCE248.
Readily available.
